A Study of the Use of Modified Collagen of Freshwater Fish as a Material for Personal Care Products

The work is devoted to the use of collagen materials produced on the basis of connective tissues of hydrobionts. Their characteristics as potential means of personal hygiene and wound healing are investigated. The results of studies of physical and chemical characteristics of collagen materials from freshwater fish with a modified structure obtained in this paper indicate the prospects of their use as an absorbent layer of personal hygiene products, due to the high moisture absorption capacity, which is an order of magnitude higher than the moisture capacity of untreated collagen and higher moisture capacity of superadsorbing polymers required for use in personal hygiene products. The resulting material meets the requirements of sanitary and epidemiological safety, allergenic action on the skin, as can be concluded from the results of tests on animals, it does not. This material accelerates reparative processes to the same extent as collagen used in standard hemostatic sponges with the simplicity of its production technology, low cost, and availability of raw materials

Влияние температур низкопотенциального источника и потребителя теплоты на эффективность теплового насоса

The article describes the experimental setup for testing a heat pump and the results of its operation at various temperatures at its inlet and outlet. An actually task is to study the operation of a heat pump under various boundary conditions, which are determined from the phase transition temperature in the evaporator and condenser. These temperatures depend on the temperature in the evaporator of a low-potential source of heat (the lower source is water, air, etc.) and the temperature in the condenser of a high-potential source of heat (the upper source is a consumer). The main indicator of the efficiency of the heat pump is the coefficient of performance. To determine the reliable value of the coefficient of performance, tests of compression heat pump were carried out. Refrigerant R-142b was used as a working fluid. Based on the experimental data, the dependences of the coefficient of performance on the temperature of the hot and cold heat source are constructed. Also, the coefficient of performance heat pump decreases when the lower heat source decreases.В статье приводятся описание экспериментальной установки для испытания теплового насоса и результаты его работы при различных температурах низкопотенциального источника теплоты и теплопотребителя. От значений этих температур в значительной степени зависит эффективность теплового насоса. Теоретическое определение параметров эффективности дает широкий разброс параметров теплового насоса из-за сложности определения внешних и внутренних потерь, поэтому экспериментальное исследование работы теплового насоса при различных температурных условиях является актуальной задачей. Главным показателем эффективности теплового насоса служит коэффициент преобразования (отношение отданной теплопотребителю теплоты к затраченной в компрессоре работе). Для определения достоверной величины коэффициента преобразования проведены испытания компрессионного теплового насоса. В качестве рабочего тела использовался хладагент R-142b. Установлено, что при увеличении температуры теплопотребителя коэффициент преобразования теплового насоса резко падает. Также коэффициент преобразования теплового насоса понижается при уменьшении температуры низкопотенциального источника теплоты

Эпидемиология эндопротезирования тазобедренного и коленного суставов и перипротезной инфекции в Российской Федерации

Background. Since there is no national arthroplasty registry in the Russian Federation, the exact number of arthroplasty operations performed is unknown. Aim of the study to evaluate the epidemiology of primary, revision hip and knee arthroplasty and periprosthetic joint infection in Russian Federation. Materials and Methods. The inquires were made to 85 subjects, 73 federal state budget institutions and 30 private hospitals. Results. Answers were received from 76 subjects of Russian Federation, 41 federal and 18 private hospitals. The studied indicators revealed to be pretty much heterogenic. The decrease of operations number from 20% to 40% in subjects of Russian Federation due to SARS-CoV-2 pandemic forced us to make no analysis for these 2020 indicators in Russian Federation generally. 147 061 primary hip and knee arthroplasties were performed in 2019 in Russian Federaion. 7 770 revison hip and knee arthroplasties were done. 6 606 cases of severe orthopaedic implant-assosiated infection were cured including 4 282 cases post hip and knee arthroplasties that constitutes 2,91 % from primary arthroplasties. Conclusions. The frequency of periprosthetic joint infection in Russian Federation correlates to the world data. High complexity for patients routing with implant-assosiated infection and strong demand for Federal Center of implant-assosiated orthopaedic infection are revealed.Актуальность. Поскольку в Российской Федерации отсутствует национальный регистр артропластики, точное число выполненных операций эндопротезирования неизвестно. Цель изучить эпидемиологию эндопротезирования коленного и тазобедренного суставов, а также перипротезной инфекции (ППИ) в Российской Федерации (РФ). Материал и методы. Сделаны запросы в 85 субъектов, 73 федеральных государственных бюджетных учреждения и 30 частных учреждений здравоохранения. Результаты. Получены ответы из 76 субъектов РФ, 41 федерального и 18 частных учреждений здравоохранения. В 2020 г. установлена значительная гетерогенность изучаемых показателей: снижение числа операций составило от 20 до 40% в различных субъектах РФ в связи с пандемией SARS-CoV-2, поэтому показатели 2020 г. решено было не анализировать по России в целом. В 2019 г. в РФ выполнено 147 061 операций первичного эндопротезирования коленного и тазобедренного суставов, 7 770 ревизионных артропластик коленного и тазобедренного суставов. В 2019 г. пролечено 6 606 случаев тяжелой ортопедической имплантат-ассоциированной инфекции, в т.ч. 4 282 случая после эндопротезирования коленного и тазобедренного суставов, что составляет 2,91% от первичных эндопротезирований. Заключение. Частота ППИ в РФ коррелирует с мировыми данными. Выявлена высокая сложность маршрутизации пациентов с имплантат-ассоциированной инфекцией и стойкая необходимость в создании федерального центра по лечению имплантат-ассоциированной ортопедической инфекции

Measurement of (anti)deuteron and (anti)proton production in DIS at HERA

The first observation of (anti)deuterons in deep inelastic scattering at HERA has been made with the ZEUS detector at a centre-of-mass energy of 300--318 GeV using an integrated luminosity of 120 pb-1. The measurement was performed in the central rapidity region for transverse momentum per unit of mass in the range 0.3<p_T/M<0.7. The particle rates have been extracted and interpreted in terms of the coalescence model. The (anti)deuteron production yield is smaller than the (anti)proton yield by approximately three orders of magnitude, consistent with the world measurements.Comment: 26 pages, 9 figures, 5 tables, submitted to Nucl. Phys.

S-band electron linac with beam energy of 30…100 MeV

The S-band electron linac has been designed at NSC KIPT to cover an energy range from 30 to 100 MeV. The linac consists of the injector based on evanescent oscillations and the two four-meter long piecewise homogeneous accelerating sections. Each section is supplied with RF power from the KIU-12AM klystron. Variation of mean energy of the beam over a wide range is produced by placing bunches out of the wave crest in the second accelerating section. The report presents layout of the linac as well as simulation results of self-consistent particle dynamics in the linac and its present status.Лінійний прискорювач електронів 10 см - діапазону було розроблено в ННЦ ХФТІ з метою перекрити діапазон енергій 30…100 MeВ. Прискорювач складається з інжектора, основаного на коливаннях, що не розповсюджуються, і двох шматково-однорідних чотириметрових прискорювальних секцій. Кожна секція забезпечується НВЧ-потужністю від клістрона KІУ-12AM. Зміна середньої енергії пучка в широких межах забезпечується прискоренням згустків не на гребені хвилі в другій прискорювальній секції. Представлено структурну схему прискорювача, результати моделювання динаміки частинок в прискорювачі і його поточний стан.Линейный ускоритель электронов 10 см - диапазона был разработан в ННЦ ХФТИ с целью перекрытия диапазона энергий 30…100 MэВ. Ускоритель состоит из инжектора, основанного на не распространяющихся колебаниях и двух кусочно-однородных четырехметровых ускоряющих секций. Каждая секция питается СВЧ-мощностью от клистрона KИУ-12AM. Изменение средней энергии пучка в широких пределах обеспечивается ускорением сгустков не на гребне волны во второй ускоряющей секции. Представлены структурная схема ускорителя, результаты моделирования динамики частиц в ускорителе и его текущее состояние

Search for pair production of boosted Higgs bosons via vector-boson fusion in the bb¯bb¯ final state using pp collisions at √s = 13 TeV with the ATLAS detector

A search for Higgs boson pair production via vector-boson fusion is performed in the Lorentz-boosted regime, where a Higgs boson candidate is reconstructed as a single large-radius jet, using 140 fb−1 of proton–proton collision data at √s = 13 TeV recorded by the ATLAS detector at the Large Hadron Collider. Only Higgs boson decays into bottom quark pairs are considered. The search is particularly sensitive to the quartic coupling between two vector bosons and two Higgs bosons relative to its Standard Model prediction, K2V . This study constrains K2V to 0.55 &lt; K2V &lt; 1.49 at the 95% confidence level. The value K2V = 0 is excluded with a significance of 3.8 standard deviations with other Higgs boson couplings fixed to their Standard Model values. A search for new heavy spin-0 resonances that would mediate Higgs boson pair production via vector-boson fusion is carried out in the mass range of 1–5 TeV for the first time under several model and decay-width assumptions. No significant deviation from the Standard Model hypothesis is observed and exclusion limits at the 95% confidence level are derived

Search for boosted diphoton resonances in the 10 to 70 GeV mass range using 138 fb−1 of 13 TeV pp collisions with the ATLAS detector

A search for diphoton resonances in the mass range between 10 and 70 GeV with the ATLAS experiment at the Large Hadron Collider (LHC) is presented. The analysis is based on pp collision data corresponding to an integrated luminosity of 138 fb−1 at a centre-of-mass energy of 13 TeV recorded from 2015 to 2018. Previous searches for diphoton resonances at the LHC have explored masses down to 65 GeV, finding no evidence of new particles. This search exploits the particular kinematics of events with pairs of closely spaced photons reconstructed in the detector, allowing examination of invariant masses down to 10 GeV. The presented strategy covers a region previously unexplored at hadron colliders because of the experimental challenges of recording low-energy photons and estimating the backgrounds. No significant excess is observed and the reported limits provide the strongest bound on promptly decaying axion-like particles coupling to gluons and photons for masses between 10 and 70 GeV

Search for heavy resonances decaying into a Z or W boson and a Higgs boson in final states with leptons and b-jets in 139 fb−1 of pp collisions at s√ = 13 TeV with the ATLAS detector

This article presents a search for new resonances decaying into a Z or W boson and a 125 GeV Higgs boson h, and it targets the νν¯¯¯bb¯¯, ℓ+ℓ−bb¯¯, or ℓ±νbb¯¯ final states, where ℓ = e or μ, in proton-proton collisions at s√ = 13 TeV. The data used correspond to a total integrated luminosity of 139 fb−1 collected by the ATLAS detector during Run 2 of the LHC at CERN. The search is conducted by examining the reconstructed invariant or transverse mass distributions of Zh or Wh candidates for evidence of a localised excess in the mass range from 220 GeV to 5 TeV. No significant excess is observed and 95% confidence-level upper limits between 1.3 pb and 0.3 fb are placed on the production cross section times branching fraction of neutral and charged spin-1 resonances and CP-odd scalar bosons. These limits are converted into constraints on the parameter space of the Heavy Vector Triplet model and the two-Higgs-doublet model

The ATLAS trigger system for LHC Run 3 and trigger performance in 2022

The ATLAS trigger system is a crucial component of the ATLAS experiment at the LHC. It is responsible for selecting events in line with the ATLAS physics programme. This paper presents an overview of the changes to the trigger and data acquisition system during the second long shutdown of the LHC, and shows the performance of the trigger system and its components in the proton-proton collisions during the 2022 commissioning period as well as its expected performance in proton-proton and heavy-ion collisions for the remainder of the third LHC data-taking period (2022–2025)

Search for single vector-like B quark production and decay via B → bH(b¯b) in pp collisions at √s = 13 TeV with the ATLAS detector

A search is presented for single production of a vector-like B quark decaying into a Standard Model b-quark and a Standard Model Higgs boson, which decays into a b¯b pair. The search is carried out in 139 fb−1 of √s = 13 TeV proton-proton collision data collected by the ATLAS detector at the LHC between 2015 and 2018. No significant deviation from the Standard Model background prediction is observed, and mass-dependent exclusion limits at the 95% confidence level are set on the resonance production cross-section in several theoretical scenarios determined by the couplings cW, cZ and cH between the B quark and the Standard Model W, Z and Higgs bosons, respectively. For a vector-like B occurring as an isospin singlet, the search excludes values of cW greater than 0.45 for a B resonance mass (mB) between 1.0 and 1.2 TeV. For 1.2 TeV < mB < 2.0 TeV, cW values larger than 0.50–0.65 are excluded. If the B occurs as part of a (B, Y) doublet, the smallest excluded cZ coupling values range between 0.3 and 0.5 across the investigated resonance mass range 1.0 TeV < mB < 2.0 TeV